4-Toluenesulfonyl chloride → 8-{4-[2-(6-Chloro-1-benzofuran-3-yl)ethyl]-1-piperazinyl}-quinoline

Participants

Reaction Steps

To a stirred solution of 2-(6-chloro-1-benzofuran-3-yl)ethanol (980 mg, 5 mmol) in anhydrous pyridine (20 ml), p-toluenesulfonyl chloride (1.14 g, 6.0 mmol) was added. The reaction mixture was kept at 0° C. for 48 hrs and quenched with ice cold water. The reaction mixture was extracted with chloroform, washed well with water and dried over anhydrous MgSO4. It was filtered and concentrated. The crude product obtained was taken to next step without any purification. A mixture of tosylate (350 mg. 1 mmol) (obtained by the above mentioned process) and 8-piperazino-quinoline (213 mg, 1 mmol) was heat at 120° C. in DMSO in the presence of N,N-diisopropylethylamine (5 ml, excess) for 24 hrs. At the end, reaction mixture was quenched with water and extracted with chloroform. The organic layer was washed with water and dried over anhydrous MgSO4 and concentrated to dryness. The dark colored solid was purified by silica-gel column chromatography by eluting it initially with 70% ethyl acetate:hexane and then with 5% methanol:ethyl acetate. 8-{4-[2-(6-chloro-1-benzofuran-3-yl)ethyl]-1-piperazinyl}-quinoline was isolated as a yellow oil. Yield: 120 mg (30%); (M+H): 392; 1HNMR (400 MHz, CDCl3):δ 8.82˜8.81 (dd, J1=1.7 Hz, J2=1.7 Hz, 1H); 8.40˜8.20 (dd, J1=1.8 Hz, J2=1.8 Hz, 1H); 7.46˜6.92 (m, 8H); 3.50˜2.70 (m, 12H).

Provenance & Evidence